Air tank fitting



June 19, 1951 w, wR|GHT ET AL I 2,557,491

AIR TANK FITTING Filed March 31, 1948 GEORGE! Ive/cur 8-. CHAL3Aimee/sou Patented June 19, 1951 AIR TANK FITTING George W. Wright andCharles Harrison, Fort Wayne, Ind., assignors to Tokheim Oil Tank & PumpCompany, Fort Wayne, 11111., a corporation of Indiana Application March31, 1948, Serial No. 18,214

4 ()laims. l

This invention relates to a discharge fitting for an air tank.

In air compressing equipment, the compressor is usually connected to astorage or absorption tank, and the compressed air is taken oil from thetank. A liquid sludge accumulates in such tanks, as from condensation ofwater and oil which is carried into it with the air delivered from thecompressor, and tanks are frequently provided with drain plugs by whichsuch sludge can be removed. The tanks are also usually provided with apressure relief valve, to keep the pressure in them within safe limits.

Our invention provides a combination fitting which may be attached to anair tank, and espe cially to an absorption tank, which combines in asingle unit all the functions of an outlet fitting, apressure-responsive relief valve, a manual pressure release valve, and asludge removing outlet. The fitting is especially applicable for use onan absorption tank, for it is customary to release the pressure fromsuch an absorption tank either when the compressor is shut down orduring starting, and in such application the invention providesautomatic sludge removal.

The accompanying drawings illustrate our invention:

Fig. l is a vertical central section of a fitting embodying ourinvention, showing the fitting in association with a tank, and showingthe valve in closed position; Fig. 2 is a vertical central section atright angles to the section of Fig. 1 and showing the valve in openposition; Fig. 3 is a plan view of the fitting shown in Fig. 1, with thehandle thereof removed, and Fig. 4 is a bottom plan of the handle.

The air compressor it delivers air through the pipe H to the tank 52,usually at a point above its bottom wall 53. When the tank I2 is anabsorption tank, it serves primarily to smooth out the pulsations whichoccur in the delivered air from operation of the compressor it. The tankI2 is provided with a collar M to receive the discharge fitting,desirably at a point directly above the lowest point of the bottom wallii; of the tank.

The delivery fitting comprises a neck l5 threaded into the collar hi anda side delivery opening it to which valved air-operated equipment may beattached and through which normal delivery of air occurs as required bythat equipment. A cylindrical housing ll, conveniently coaxial with thedelivery passage through the neck I5, is formed on that neck above thedelivery opening I6. The dividing wall between the housmg I! and theneck I5 is formed to provide an upstanding valve seat rim I8. Within therim ill the dividing wall is bored to provide a hole l9 of less diameterthan the passage through the neck l5, and the upper end of that hole I9is counterbored to form a shoulder 2!! in that hole below the valve seatit. A tube 2! is fixed in the hole l9 and extends downwardly through thepassage in the neck 15, and substantially to the bottom wall l3 of thetank. The tube may conveniently be secured in place by expanding itsWalls below the dividing wall and flaring its upper end over theshoulder 20. V

A valve member 22 loosely received in the valve chamber within thehousing ll seats on the valve seat It. A cover 23, desirably with adepending flange 2t fitting against the walls of the housing I? issecured on the housing, as by means of screws 25 through the wall llinto the flange 24. A plunger 26 is slidably and rotatably mounted inthe cover 23 over the cent-er of the valve member 22. Its lower endcarries a valve engaging head 27, and the plunger 26 is surrounded by aspring 28 urging the head 2'! downwardly against the valve member 22,and reacting against the top wall of the cover 23.

The upper end of the head 23 is formed to provide a pair ofdiametrically opposite, flattopped cams 29. A handle 30 is secured tothe upper end of the rod 27 and has on its under face a pair ofcam-engaging lugs 3!. In closed-valve position, the lugs 3! lie freebetween the two cams 29. A quarter turn of the handle moves the lugs 3|up the cam surfaces of the cams 3B and onto the flat tops of these cams,which lifts the plunger 26 against the spring 25?, to retract the head2'! upward and release the valve member 22 for movement away from itsseat IE One or more discharge openings 32 are formed through the wall I!adjacent the valve member 22.

Operation is as follows: It is assumed that some air operated equipment,such as a spray gun or a grease gun, is attached to the fitting at theopening 5 ii, and that the air control valve of that equipment isclosed. Before starting the compressor Ill, the handle 30 is desirablymoved to or through valve releasing position, which releases any airpressure in the tank 12, as will appear. If the valve is left in openposition during the starting, it is then closed. Operation of thecompressor builds up air pressure in the tank, and upon demand of theair operated equipment, air under pressure is delivered through theannular passage between the tube 2! and the neck I5 and through thedelivery opening it to the air operated equipment. If the air pressureexceeds the amount predetermined by the tension of the spring 28, thepressure lifts the valve 22 from its seat l8 and permits a pressurerelease. During such pressure release, the path of flow is into thelower end of the tube 2| adjacent the bottom wall l3 of the tank l2, andupward through that tube 2| to the counterbore within the valve seat l8,thence between the valve seat l8 and the valve member 22 to the valvechamber within the housing [1, and thence to atmosphere through theopenings 32.

When use of the equipment is stopped, pressure in the tank I2 isreleased by turning the handle 30 to or through valve releasingposition. Again, the path of flow for this release is into the bottomend of the tube 2|, upward through that tube, past the valve 22, and toatmosphere through the openings 32.

In any such release of pressure in the tank l2, either because the valve22 is lifted by excess pressure or by operation of the handle 30, thepath of flow from the tank is through the bottom end of the tube 2|. Thebottom end of that tube 2|, being positioned close to the bottom wall l3of the tank |2, will be submerged in any accumulation of liquid sludge,and as a result any flow which occurs will automatically cause adischarge of the accumulation of sludge. Thus, normal and usualoperation of the air compressing equipment will automatically preventprogressive accumulation of sludge in the tank, and will dischargesludge through a path which, though provided by the single fitting, willbe wholly separate from the normal air delivery passage.

We claim as our invention:

1. A combination fitting adapted to be attached to an air tank above itsbottom, a passage therein to receive air from the tank, a passagetherefrom for normal delivery of air, a valve chamber out ofcommunication with said passages, a pressure relief and clean-out tubeextending from said valve chamber through the air-receiving passage ofsaid fitting and having an inlet opening at a point adapted to lieadjacent the bottom of the air tank, a valve seat about the opening ofsaid tube into said valve chamber, a valve member loosely received insaid valve chamber in position to engage said seat, a cover on saidvalve chamber, a plunger movably mounted in said cover and yieldinglyurged against said valve to seat it on said seat, a manually operablehandle on the plunger, and cam means between said handle and said coverto retract the valve engaging member from the valve.

2. A combination fitting adapted to be attached to an air tank above itsbottom, comprising a nipple having an air delivery passage adapted todeliver air from the tank, a valve chamber out of communication withsaid passage, an air-relief and clean-out conduit through said nippleand adapted to open to said tank at a point adjacent the bottom thereof,said conduit leading to the valve chamber out of communication with theair-delivery passage, a valve seat about the valve-chamber end of saidconduit, a valve member on said seat, a springpressed plunger urgingsaid valve to seated position and movable thereby in response to excessair pressure, and manually operable means for retracting said plungeragainst its spring to release the valve member.

3. A combination fitting for an air tank, comprising a nipple adapted tobe sealed to the tank at a point above its bottom, an axial passage insaid nipple open at its tank end, a lateral airdelivery passagecommunicating with said nipple passage, an air relief and clean-out tubeextending through said nipple passage and of smaller cross sectionalarea than said nipple passage, said tube extending through the end Wallof said nipple passage and forming a passage out of communication withthe air delivery passage and adapted to communicate with the tank at apoint adjacent the bottom thereof, a valve seat formed in said end-wallabout the end of said tube, upstanding valve-retaining walls about saidseat, a valve member loosely received within said walls on said seat, acover removably mounted on said walls, a plunger carried by said coverand spring pressed against said valve, a rotatable handle fixed to theouter end of said plunger, and cam means between said handle and coverand operable upon rotation of said handle to retract the plunger fromthe valve.

4. A combination fitting for an air tank, comprising a housing adaptedto be attached to the air tank at a point above its bottom, a conduitprojecting therefrom and adapted to open to the tank at a point adjacentthe bottom thereof, a separate air delivery passage in said housing, adischarge passage separate from said air delivery passage, apressure-responsive valve in said housing between the outer end of saidconduit and said discharge passage, and a handle operative to releasesaid pressure responsive valve to vent said tank through the bottomopening of said conduit.

GEORGE W. WRIGHT. CHARLES HARRISON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 382,329 Seymour May 8, 1888674,675 Fernald May 21, 1901 753,324 Shanklin Mar. 1, 1904 1,421,319Stern June 27, 1922 1,575,547 Conrad Mar. 2, 1926 2,083,964 Schulz June15, 1937

